Tank deck



Mayz, 1933- w. s cHwEMLElN 1,907,268

TANK DECK Filed Aug-` 5, 1951 gwuemtcw Patented Mey 2, 1933 UNITED s'IA'ATasA PATENT# OFFICE# WILLIAMY sonwenn.IIIN, or PAnxERsBURG, was/.U 'VIRGINIA` AssIoNon THE PARKERSBURG RIG AND -maar. COMPANY, or IAxnasnnwasr- VIRGINIA, A-

CORPQRATION OF WEST VIRQINLA Y TANK DECK y V.Application tiledV August 3, 1931. Serial No. 554,890.

This invention relates to tank deck constructions, and more particularly to aconstruction for the decks of large oil storage tanks. l Y Y In the oil industryit is the common practice to employ large storage tanks havin capacities of 100 barrels and upwardly,an the constructionv ofthe parts of'these tanks,

as well as their erection vandmaintenance involves considerable expense. pacities of such tanks they necessarily are of substantial diameters, and one of the 'most important items in the expense of manufacturing the tanks lies in the construction of the tops or decks thereof. The decks usually` are fa ricated from rectangular metal sheets ,with portions thereof forming the edge of the deck curved to conform to the cross sectional shape of the tank. The deck thus provided is supported by a plurality of metal anglesY arranged radially with respect to the tank, and it has beenfound that the cost of these rafters amounts to approximatelyt perl cent of the cost of the average size tank.`

The rafters employed in the deck constructions merely support the deck against downward movement, and .thus the weight ofthe deck is taken care of, andthe tendency of the deck to move downwardly is prevented when a partial vacuum is 4created in the tank due to the contraction of the contents thereof,y

occurring Vwhen a drop in temperature takes place. However, no provision is made for preventing the deck-from vrising when the contents ofthe tank expand under increased` temperature conditions, it having been found impracticable to bolt the deck plates to the rafters due to the expense for materialand labor involved in the use of a 'sufficient number of bolts to accomplish the desired result.

The decks are free to move upwardly, there- `fore, and. it requires only a Vfew ounces of A further object is to provide a deck con- Due to the ca.

the tank, n 1

, Figure 4 isl a plan `view -of one of thedeck` struction Vfor -tanks wherein vertical m0vement of the deck is resisted both upwardly and downwardly when expansion or contraction takes place in-'the contents of the tank.

A further object isl to providea deck con struction of the character referred to which possesses all of the advantages of the presentA deck constructions without the disadvantages thereof, and wherein the cost and time-involve'd in the manufacture and erection of the tank is reduced while the yuse* of the usual metal rafters is eliminated.

A further object is to provide a tank .deck which possesses a substantial` degree of rigidity against vertical movement and which effectively braces the tank against lateral distortion which would alter` `its cylindrical shape, without the use `of the usual metal rafters. c L: v l

, Other objects and advantages of the invention will become apparentduring the course ofthe `following description.

In the drawing I have shown one embodiment of the invention.` In this showing: Figure 1 is a perspective viewof the top of an oil storage tank, showingthe deck in position thereon,v f j; l Y Figure 2 is anenlarged fragmentary vertical sectional view to the 'topof the tank, taken radially with respect to the tank,v

. Figure 3 is a similar view showing the connection between the deck and side plates of sheets,

Figure 5 is an enlarged tary sectional view on line 5--5 of Figure 4,

Figure 6 is a similarview online 6 6 of Figure 4, y

Figure 7 is a similar viewon line 7 7. of

Figure 4, and ..1 r

Figure 8 is a detailed sectional viewshowing the connection between two adjacent deck .f

plates. I

Referring tothe drawing numeral 10 designates the body of the tankwhich may be f made up of' a plurality of.y plates secured together at their edges in any suitable manner. The construction of the` body of the tank forms no part of the present invention. f

detailed fragmeil- The deck of the tank is indicated as a whole of segmental plates 12 one of which is shown in detail in Figure l. Each plate 12 has its Side ed es substantially radial with respectto the tani, while the outer edge 13 of each plate is curved to conform to the curvature of the body of the tank. The inner edge of each deck plate is curved as at 14 for a purpose to' be described. The plates forming the upper end of the body 10 are turned outwardly to form flanges 15 to support the deck plates 12 as shown in Figure 3. Bolts 16 secure the edge portions 13 of the-deck vplates to the flanges 15, suitable packing 17 being arranged between these members to provide la leakproof `oint.

Eac deck platel 12 is provided with a pluralityl of ribs 18 extending substantially radially with respect tothe tank and terminating relatively short distances from the edges 13 and 14 of each deck plate. As'shown in Figures 5,6 and- 7, the ribs 18 increased both in de ofthe tank. .The ribs 18 serve to reinforce the de'ck and thebody of the tank in a manner to be described.

.The plates 12 are secured to'each other in the manner shown in Figure 8. Each plate 12 is provided at both of its side edgeswith reinforcing ribs 19, the rib 19 at one edge'of each .plate registering with the corresponding rib atthe edge of the next adjacent plate, as shown in Figure 8. Packing 20 is arranged between the overlapping edges of the sheets 12, and bolts 21 pass through the overlapping edges and through'the packing to secure these elements together and to provide a leak-proof joint. The inner face of the lower rib 19, in

eachl instance, forms a channel 22 to receive the head 230i each bolt 21 whereby the bolt is prevented from turning when its nut 24 is` tightened.

The tank is rovided with a dome indicated as a whole by t e numeral 25. The dome comprises a cylindrical body 26 having outstanding flanges 27 and 28 at itsupper and lower ends, as shown in Figure 2. Packing 29 is arranged between the flange 28 and the deck plates 12, and these elements are secured together by bolts 30. v

A cover plate 31 is arranged at the top of the dome and is secured to the flange 27 by bolts 32, packing 33 being arranged between the flange 27 and cover plate 31.

The operation of the deck willbe apparent from the foregoing description. The use of the `usual mtal rafters is completely eliminated, it having been found that a substantial degree ,ofy rigidity against vertical movement of the deck is provided by the reinforcingk ribs 18. These ribs are increased inv width and depth toward their outer ends to provide additional rigidity where the ribs are spaced further apart. It has been found that h and width towardthe outside vextent to permanently distortthe deck plates.

Moreover, it hasl been found that the use of radial'joints between the'de'ck Isheets also tends to prevent permanent distortion of the plates, while resistance to vertical movement and distortion also isgreatly increased by the use. of the overlapping channel joints between the deck plates themselves, as shown in Figure 8. The use of sucha channel construction also permits leakage from the tank to be more effectively prevented by causing the packing 20to 'assume Vthe shape of the ribs 19, while the channel 22 permits the nuts 24 to be tightened aftererection of the tank without permitting the bolts 21v to turn, to eliminate` any leakage which may occur between the deck plates. v

The edges 14 of the deck'plates combine to define a circular opening corresponding in shape andsize to theopeningthrough the'. dome.l The sloping of the deck together. with the features of reinforcement referred to permitsthe dome to be directly secured to the inner ends of the deck plates without the use of the usual angle iron braces employed for stiiiening the deckat the point where the dome is secured thereto. f f

Italso has been found thatthe rigidity of the deck construction is such as to prevent radial distortion of the top of the tank from its true'cylindrical form, and thus afurther necessity for the use of rafters is eliminated.

From the foregoing it will be apparentthat the present construction embodies allof the advantages of the usual deck constructions, and in addition thereto, provides means for resisting distortion of the deck due to the accumulation of pressure therein when expansion of the contents of the tank takes place. Thus a large item in the manufacturing cost of the tank is eliminated since it is wholly unnecessary to employ the rafters. Moreover, the elimination of the rafters also re-l duces the time and the cost of'la-bor involved in the erection of the tank.

While I have described in detail therpreferred embodiment of my invention itis to be understood that various changes in the size, shape and arrangement of parts may be resorted to without'departing from the spirit of the invention orthe scope of the subjoined claims. y

Iclaimpl. lA tank deck plate comprising 'a substantially planiform sheet of substantially segmental shape provided 4adjacent one lateral edge with a channel-like portion offset from the plane of the body of the sheet to form a substantially radial relatively shallow joint member designed to register with a corresponding member of an adjacent sheet, said joint member extending throughout the greater portion of the length ofthe sheet and terminating inwardly of the outer end thereof, said sheet having a continuous substantially planiiorm portion on opposite sides and radially outwardly of said joint member adjacent the outer end thereof.

2. A tank deck plate comprising a substantially planiform sheet of substantially segmental shape provided adjacent one lateral edge with a channel-like portion oifset from the plane of the body of the sheet to form a substantially radial relatively shallow joint member designed to register with a corresponding member of an adjacent sheet, said joint member extending throughout the greater portionof the length of the sheet and terminating inwardly of the outer end thereof, said sheet having a continuous substantially planiform portion on opposite sides and radially outwardly of said joint member adjacent the outer end thereof, said sheet being further provided intermediate its width with a rib offset from the plane of the sheet and extending radially thereof with its outer end spaced from the outer end of the sheet, said rib progressively increasing in width and depth from its inner end toward its outer end.

3. A tank deck comprising a plurality of substantailly pl aniform sheets of substantially segmental shape having their lateral edges overlapping and each provided adjacent each lateral edge with a channel-like portion oli'- set from the plane of the body of the sheet to form a substantially radial relatively shallow joint member designed to register with the adjacent joint member of the adjacent sheet, each joint member extending throughout the greater portion of the length of the sheet and terminating inwardly of theouter end thereof, each sheet having a continuous substantially planiform portion on opposite sides and radially outwardly of each joint member adjacent the outer end thereof, and

packing arranged between each pair of overlapping edges. Y K

4. A tank deck comprising a plurality of substantially planiform sheets of substantially segmental shape having their lateral edges overlapping and each provided adjacent each lateral edge with a channel-like portion offmember adjacent the outer end thereof, each I set from the plane of the body of the sheet to form a substantially radial relatively shallow joint member designed to register with the adjacent joint member of the adjacent sheet, each joint member extending throughout the greater portion of the length of the sheet and terminating inwardly of the outer end thereof, each sheet having a continuous substantially planiform portion on opposite sides and radially outwardly of each joint ywo 

